The present invention relates to an apparatus and a method for measuring rotation quantity of a spherical object.
In a conventional method for measuring rotation quantity of a spherical object, rotation quantity of a spherical object (a spinning spherical object) having an unspecific rotation axis such as a golf ball or a tennis ball is obtained by measuring rotation quantities on respective axes of a three-dimensional coordinate-system using an apparatus as shown in FIG. 6.
In the conventional method, picture recording devices 100, 101, and 102 (for example, cameras) are fixed on three axes x, y, and z intersecting perpendicularly with one another, a spherical object 103 to be measured is photographed for plural times at predetermined intervals, and the rotation quantities on the axes are respectively analyzed using the photographed pictures.
The measuring method shown in FIG. 6 requires three picture recording devices, therefore the measuring apparatus as a whole becomes large, and moreover, it is difficult to fix the picture recording devices at positions intersecting perpendicularly with one another in case of outdoor measurement. It is apprehended that the object to be measured (i.e. the spherical object) moves toward one of the picture recording devices, and in this case, there is a high possibility of colliding with the picture recording device and damaging the device. In addition, the method requires analysis for each of the three picture recording devices.
It is therefore an object of the present invention to provide an apparatus for measuring rotation quantity of a spherical object, in which the apparatus as a whole is compact, the installation is easy, and rotation quantity is measured with high accuracy.
It is another object of the present invention to provide a method for measuring rotation quantity of a spherical object, in which rotation quantity is measured easily with high accuracy.